Dye discharge reagent for inkjet compositions

Abstract

A process of in situ forming a dye discharge reagent on at least a portion of surface of a dyed substrate, effected by applying two or more compositions comprising reactants on the substrate, such that the reactants undergo a chemical reaction on the substrate to form the reagent is provided herein, as well as a method for dye discharging a dyed substrate using the process of in situ forming a dye discharge reagent, and a dye discharge composition comprising said dye discharge reagent. In some embodiments of the invention, the reactants are thiourea and a peroxide, and the dye discharge reagent is formamidine sulfinic acid (FSA).

1 . (canceled) 
     
     
         2 . A method of discharging a dye in a dyed substrate, comprising contacting at least a portion of said substrate with a first composition and a second composition, wherein said first composition comprises a first reactant and said second composition comprises a second reactant, said first reactant and said second reactant undergo a chemical reaction to form a dye discharge reagent in situ on the substrate, thereby discharging the dye in the substrate with said dye discharge reagent, and wherein said contacting is afforded by separately applying said first composition and said second composition on said portion. 
     
     
         3 . (canceled) 
     
     
         4 . The method of  claim 2 , wherein said first reactant and said second reactant are applied at a stoichiometric ratio. 
     
     
         5 . (canceled) 
     
     
         6 . The method of  claim 2 , wherein each of said first composition and said second composition is individually applied on said portion of the substrate by a separate inkjet printhead. 
     
     
         7 . (canceled) 
     
     
         8 . The method of  claim 2 , wherein said applying is effected concertedly, concomitantly or sequentially. 
     
     
         9 . (canceled) 
     
     
         10 . The method of  claim 2 , further comprising heating and/or irradiating at least said portion of the substrate subsequent to said contacting. 
     
     
         11 - 12 . (canceled) 
     
     
         13 . The method of  claim 2 , wherein said first reactant is thiourea and said first composition is an aqueous solution of said thiourea. 
     
     
         14 . The method of  claim 13 , wherein said second reactant is a peroxide and said second composition is an aqueous solution of said peroxide. 
     
     
         15 . The method of  claim 14 , wherein said dye discharge reagent formed in situ is formamidine sulfinic acid (FSA). 
     
     
         16 . (canceled) 
     
     
         17 . The method of  claim 15 , wherein a concentration of said thiourea in said first composition ranges from 5-25%. 
     
     
         18 . The method of  claim 15 , wherein said peroxide is selected from the group consisting of hydrogen peroxide, peroxymonosulfuric acid, a peroxomonosulfate salt, a peroxydisulfate salt, an organic peroxy acid, an organic peroxide, an organic hydroperoxide, a perester and a transition metal peroxide. 
     
     
         19 . The method of  claim 18 , wherein a concentration of said peroxide in said second composition ranges from 5-50%. 
     
     
         20 - 22 . (canceled) 
     
     
         23 . A kit comprising a packaging material and the inkjet dye discharge composition that comprises a first composition and a second composition, wherein said first composition is an aqueous solution of thiourea and said second composition is an aqueous solution of a peroxide. 
     
     
         24 . The kit of  claim 23 , being identified for use in discharging a dye in a dyed textile substrate. 
     
     
         25 . The kit of  claim 23 , being identified for use in a method of inkjet printing an image on at least a portion of a dyed textile substrate. 
     
     
         26 . The kit of  claim 23 , wherein said first composition and said second composition are packaged individually within the kit. 
     
     
         27 . The kit of  claim 26 , further comprising instructions that comprises:
 loading said first composition to a first printhead;   loading said second composition to a second printhead; and   contacting said first composition with said second composition by inkjet printing said first composition and said second composition on a substrate.   
     
     
         28 . The kit of  claim 25 , further comprising a translucent colored composition packaged individually within the kit. 
     
     
         29 . The kit of  claim 25 , further comprising an opaque underbase composition packaged individually within the kit. 
     
     
         30 - 31 . (canceled) 
     
     
         32 . A process of inkjet printing an image on at least a portion of a dyed textile substrate, the process comprising digitally applying onto at least a portion of a substrate a inkjet dye discharge composition that comprises a first composition and a second composition, and digitally applying substantially over said portion a translucent colored composition, thereby forming the image, wherein said first composition is an aqueous solution of thiourea and said second composition is an aqueous solution of a peroxide. 
     
     
         33 . The process of  claim 32 , further comprising, prior to applying said translucent colored composition, digitally applying an opaque underbase composition substantially over said portion. 
     
     
         34 . The process of  claim 32 , wherein applying said dye discharge composition and applying said translucent colored composition, and/or applying said dye discharge composition and applying said opaque underbase composition, if present, is effected substantially concurrently. 
     
     
         35 . The process of  claim 32 , subsequent to said applying, heating the substrate.